Microbiota and rational empirical antibacterial therapy of anorectal abscess

AIM: to characterize the microbiota composition of anorectal abscess and determine the optimal empirical antibiotic therapy strategy based on microbial culture data with antibiotic susceptibility testing.

PATIENTS AND METHODS: following incision and drainage of an anorectal abscess in 149 patients, samples of wound exudate were collected from postoperative wounds by swab method and subjected to bacteriological analysis. In 102 cases, only monocultures were isolated, and in 10 cases, the association of two microorganisms was observed. The absence of microbial growth was noted in 37 cases.

RESULTS: among the identified microorganisms, the most prevalent were Escherichia coli (51.68%), Klebsiella pneumoniae (12.75%), and Staphylococcus aureus (7.38%). Less frequently encountered pathogens included Enterococcus faecalis (6.04%), Enterobacter cloacae (3.36%), and Pseudomonas aeruginosa (3.36%). The assessment of the isolated microorganisms' susceptibility to a range of antibiotics allowed us to determine the weighted average efficacy of each drug against the microbiota identified.

CONCLUSION: the combination of ciprofloxacin and clindamycin demonstrated high clinical and economic efficacy, making it a preferred empirical therapy in patients with severe form of anorectal abscess.

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